The prior art in connection with the field of window coverings such as pleated shades is replete with products many of which have been in existence for a very long period of time. From their earliest embodiments, these products have included cellular shades with various creases and pleats so as to form an accordion configuration, either in a single sheet or in multiple sheet configurations, and in connection with cellular shades which also include such creases or pleats. In connection with these cellular products, these include structures which are prepared from separate tubes or strips folded into tubular configurations and adhered together serially to form longitudinally extending cells such as those disclosed in U.S. Pat. Nos. 3,963,549 and 4,603,072. Further cellular structures are disclosed in U.S. Pat. Nos. 4,288,485 and 4,346,132, in which a number of sheets are stacked and adhered together along spaced bands forming a number of cells between adjacent sheets. Such cellular structures are also prepared from sheets which are longitudinally folded and adhered together so that each sheet forms a part of two adjacent cells. These include such structures as are shown in U.S. Pat. Nos. 4,631,217 and 4,677,012. Additionally, cellular structures can be prepared from two folded sheets disposed at opposite sides of the shade and connected together at spaced locations as in U.S. Pat. Nos. 2,201,356 and 4,625,786, for example. Also, cellular structures have been formed from single continuous sheets of material which are bonded together at spaced intervals to form adjacent cells arranged in double row configurations as in U.S. Pat. No. 4,347,887.
Again, in each of these cases, the creases or pleats are actually formed at both locations where the shade is to be folded upon its closure or collapse.